Generally, as wireless cellular networks advance, such as beyond IMT-2000 or toward IMT-Advanced, wireless relaying technology has the potential to become increasingly used. These advanced wireless networks are generally accompanied with an increased operating carrier frequency. The increased carrier frequency generally results in greater signal attenuation that in turn may cause smaller cell sizes within the network. To combat the decreased cell sizes, wireless relaying may be used to propagate signals to a distance from a base station that the base station would otherwise be unable to service by itself. When wireless relaying is typically used, a single relay station is located between a base station and a wireless subscriber station, which is also called a mobile station or terminal. The base station generally transmits a signal to the relay station, and then the relay station will transmit the signal to the mobile station. This system is also known as a multi-hop network, where each link in the transmission of the signal is a hop. Other systems may include three or more hops in the transmission of the signal where two or more relay stations transmit signals serially between the relay stations.
The receive-and-transmit process of the relay station is what has become known in the art as half duplex mode. In half duplex mode, the relay station will in an alternating manner receive a signal from the base station and then transmit the signal to the mobile station in a time division multiplexing (TDM) fashion. In this mode, the base station and the mobile station are generally idle, in terms of transmitting or receiving signals, half of the time. For example, the mobile station typically is idle when the base station transmits to the relay station, and the base station is typically idle with regard to the particular mobile station when the relay station transmits to the mobile station.
The throughput of data to the mobile station is generally constrained because the base station and the mobile station are typically idle for such a significant amount of time in this half duplex mode. This constraint may adversely affect an end user at the mobile station, such as by inability to receive a sufficient amount of data or by delay in transmitting a large amount of data. Thus, there is a need in the art to obviate the deficiencies of this half duplex mode by the realization of a feasible and practical full duplex mode.